Implementing an Operating Strategy

Energy Management Strategies are handled by the Energy Management Systems (EMS). To implement a new strategy, additions in multiple places are necessary.

1. Adapt the EMS_model.py file and implement the operating strategy

Create a new class that is inherited from the general HEMS class. Don’t forget to add the strategy in the valid parameter of the HEMS ABC class. You can also inherit from subclasses of the HEMS class like HEMS_default to also be able to inherit their methods and properties.

eelib/core/control/EMS/EMS_model.py (01/24)

class HEMS_default(HEMS):
    """Default strategy for Energy Management System.
    Should be copied and adapted for the use of a specific EMS concept.
    """

    @classmethod
    def get_valid_parameters(cls):
        """Returns dictionary containing valid parameter types and values.

        Returns:
            dict: valid parameters for this model
        """

        # use parent's parameter list and modify them for this class
        result = HEMS.get_valid_parameters().copy()
        result.update({})
        return result

    def __init__(self, eid: str, step_size: int = 900, **kwargs):
        """Initializes the eELib HEMS default model.

        Args:
            eid (str): name of the entity to create
            step_size (int): length of a simulation step in seconds
            **kwargs: initial values for the HEMS entity

        Raises:
            ValueError: Error if selected strategy does not comply with model type.
        """

        # check given strategy
        if "strategy" in kwargs.keys() and kwargs["strategy"] != "HEMS_default":
            raise ValueError("Created a HEMS_default entity with strategy not 'HEMS_default'!")
        else:
            kwargs["strategy"] = "HEMS_default"  # set strategy if not already given

        # call init function of super HEMS class
        super().__init__(eid=eid, step_size=step_size, **kwargs)

Add a step() function that first calls the HEMS step() and afterward implement the functionalities of your operating strategy.

eelib/core/control/EMS/EMS_model.py (01/24)

def step(self, timestep):
    """Calculates power set values for each connected component according to the strategy.

    Args:
        timestep (int): Current simulation time
    """

    # execute general processes (aggregation of power values etc.)
    super().step(timestep)

    # from here on: execute strategy-specific processes
    ...

---

2. Add the strategy and its input to the model_data of the scenarios

examples/data/model_data_scenario/model_data_building.json (01/24)

{
    "ems": [
        {
            "strategy": "HEMS_default",
            "cs_strategy": "balanced"
        }
    ],
    ...

---

3. Add your EMS class to the model_connections/model_connect_config.json file

Add the data that is sent out…

eelib/model_connections/model_connect_config.json (01/24)

"HEMS_default": {
    "PVLib": [["p_set_pv", "p_set"]],
    "BSS": [
        [
            "p_set_storage",
            "p_set"
        ]
    ],
    "ChargingStation": [
        [
            "p_set_charging_station",
            "p_set"
        ]
    ],
    "Heatpump": [
        [
            "p_th_set_heatpump",
            "p_th_set"
        ]
    ],
    "grid_load": [["p_balance", "p_w"], ["q_balance", "q_var"]]
},

… but also to every model, which data is sent to your HEMS!

e.g. but not only the BSS

"BSS": {
    "HEMS_default": [
        [
            "p_discharge_max",
            "p_min"
        ],
        [
            "p_charge_max",
            "p_max"
        ],
        [
            "p",
            "p"
        ]
    ],
    ...
},

---

4. Add the model with its name and (input/output) attributes to the META of the EMS_simulator

eelib/core/control/EMS/EMS_simulator.py (01/24)

META = {
    "type": "hybrid",
    "models": {

        "HEMS_default": {
            "public": True,
            "params": ["init_vals"],
            "attrs": [
                "q",
                "p",
                "p_max",
                "p_min",
                "p_set_storage",
                "p_set_charging_station",
                "p_set_pv",
                "p_balance",
                "q_balance",
                "bss_data",
                "pv_data",
                "cs_data",
                "p_th",
            ],